Royal River dam history

The town of Yarmouth, Maine is considering what to do with two dams on the Royal River.  The town owns the dams near Bridge Street and East Elm Street; these dams, or their predecessors, were built as early as the mid-1700s to provide mechanical hydropower to the industrial mills that played a large part in the local and regional economy.  Since 1674, settlers used the Royal River's waters to power mills; as early as 1759, a dam at East Elm Street was used to impound water to power an iron mill.  The debate over whether to repair or remove the dams is grounded in the history of human use of the Royal River's hydropower resources.

One of the best historical texts on Maine's hydropower potential and resources is The Water-Power of Maine, a compilation of reports by the commissioners of the Hydrographic Survey of 1867 and its secretary, Walter Wells.  The report broadly identifies 1,955 "water-powers" based on a survey asking municipalities about the resources within their boundaries.

For Yarmouth, the report provides the following description along with a note that the information was "digested from Selectment's Returns":

SIX POWERS.

They are called, - one, "Gooch's"; four, "Baker's"; one, the "Factory Fall".  All are situated on Royal's River; combined height, sixty-six feet in one mile.

Power estimated sufficient to grind seventy-five bushels of grain per hour each. Power is not all improved; mills work all the year; machinery not the best.

Stream connected with three small ponds. Range from lowest to highest water, eight feet. Effect of the improvement of the power upon the wealth of the town, excellent.

This snapshot gives us a good look at the water-power of Yarmouth in 1867. (Compare the elegant sign prepared by the Yarmouth Village Improvement Society in 2011, showing a map and images from industrial activities at four of the natural water-power sites in Yarmouth.) A twenty-first century visitor to Yarmouth might be surprised at the industrial history of the waterway, including a large pulp mill owned by the Forest Paper Company, textile mills, and other manufacturing concerns that employed the people of Yarmouth over the years.

140 years later, the Royal River's waters do not grind much grain, but at least two of the dams remain in the river. In 1984, the Sparhawk Mill near to the Bridge Street dam installed hydroelectric generation, although it is reportedly worse for the wear and produces little to no useful power. (Perhaps "machinery not the best" could have been said about the present-day site as well as it was in 1867.)

Dam removal advocates have labeled the dams "relics of an industrial age". Environmental advocates suggest that Yarmouth remove the dams, given the cost of maintaining them, their impacts to fish in the river, and the fact that they are not fully being used to produce renewable power.  Yet Yarmouth has a strong culture of interest in both sustainable energy (e.g. Yarmouth Energy Savers Committee) and historical preservation (e.g. Yarmouth Historical Society); the town's consultants found that the dams could generate some renewable electricity, and could be eligible for inclusion in national historic preservation districts.  Given the history and present risks and opportunities, will the people of Yarmouth choose to remove the Royal River dams?

Will Yarmouth remove dams?

The town of Yarmouth, Maine holds a public hearing tonight on whether to remove two town-owned dams in the Royal River. The dams near Bridge Street and East Elm Street were built long ago to impound water and provide power to mills along the river's course to Casco Bay.  As early as 1759, an iron mill used hydropower produced by the East Elm Street dam's predecessor.  Over time, the dams were updated; in 1984, hydroelectric generation was installed at the Sparhawk Mill adjacent to the Bridge Street dam.

Last fall, dam removal advocates and the town held several meetings to discuss their removal.  Although the dams are equipped with fishways operated by the Maine Department of Marine Resources, environmental and fisheries advocacy groups consider them nonfunctional.

At a December 2011 workshop, all five of Yarmouth's town councilors who were present agreed that the dams should be moved.  To move forward with dam removal, the town will need both financing and regulatory approvals.

Tonight, the dam removal proposal faces a public hearing.

Could net metering save municipal hydro?

Two dams on the Royal River in Yarmouth, Maine are one step closer to removal, as a majority of the town council agreed earlier this month that the dams should be removed.  The town owns two dams near Bridge Street and East Elm Street, which provided mechanical power to mills as early as 1816.  The Sparhawk Mill site near Bridge Street was upgraded to produce hydroelectricity in 1984, and operates as a privately-owned hydroelectric project exempt from most Federal Energy Regulatory Commission regulation.  Yarmouth has considered dam removal for several years, with concerns over fish habitat restoration as the driving factor.

The push to remove the dams comes despite the value of the sites' ability to generate renewable electricity.  A consultant hired by the town in 2010 estimated that the Bridge Street site could theoretically produce over $150,000 in annual hydropower revenues (7 page PDF), with $55,000 being a more realistic estimate of practical production from the existing facilities if they could be repaired and maintained.  In reaching this figure, the report assumed the then-current energy price of 7 cents per kilowatt-hour (kWh).  The report also assumed that the project could qualify for net metering, which the report defined as "unused power is purchased by the utility".

Maine's style of net metering at present is slightly different from that suggested in the report.  Under what Maine calls net energy billing, the owner of eligible renewable or micro combined heat and power (CHP) equipment can use the generation facility to offset its consumption of electricity from the grid, effectively running its electric meter backwards.  If a customer generates more electricity than it uses in any given month, the utility banks the excess amount as credits to be used within the next year.

One advantage gained by a net metering customer is that when generation offsets consumption, the customer saves on more than just the energy component of its electric bill.  In Maine's electricity market, customers pay for both the energy they use and what it costs to deliver that energy over transmission and distribution wires.  Today, the standard offer energy price for residential and small commercial customers in Central Maine Power's territory (including Yarmouth) is 7.4 cents per kWh.  The Maine Public Utilities Commission reports that delivery fees add another 6.47 cents per kWh for residential customers, or 6.3 cents for small commercial customers.  Thus the total cost to these customers of buying electricity and having it delivered is closer to 13.7 cents per kWh - nearly double that assumed in the town's report.  This higher figure may more accurately reflect what the town could save by net metering the Sparhawk Mill project's output against its consumption.

Maine also allows more than one customer to cooperate in net metering.  One eligible generation project can be used to offset consumption on up to 10 customer accounts, provided the participating customers establish partial ownership or an entitlement to the part of the project's output.  This shared ownership net metering lets eligible projects reach their full potential, even when they can produce more electricity than the primary owner needs in a year.

If the town can take the full value of net metering into account and find a way to benefit from the existing renewable generation at the Sparhawk site, the economics would tip towards keeping the Sparhawk project running.  There are other ways that project revenues could be boosted by smart participation in other energy programs, such as selling capacity or renewable energy certificates (RECs) if the project can be certified as renewable.

Would reevaluating the Royal River dam's hydropower potential lead the town to a different conclusion on whether the dam should be removed?  The Yarmouth town council is holding a workshop session on January 5 and a public hearing on January 19 to discuss next steps.

Yarmouth, Maine considers dam removal, other options

The town of Yarmouth, Maine is holding a meeting on November 1, 2011 about the future of two town-owned dams on the lower Royal River.

The Royal River flows nearly 40 miles across Maine, from Sabbathday Pond in New Gloucester to meet Casco Bay in the town of Yarmouth.  Along this course, the Royal River falls about 300 feet, much of which forms a series of old dams and falls in its lower reaches.  The village of Yarmouth formed around several of these dam sites, which provided mechanical power to mills and businesses in the village.  Today, dams remain on the Royal River.  A non-hydropower dam spans the river near East Elm Street, while the Sparhawk Mill dam hosts hydroelectric generating facilities near Bridge Street.

The Sparhawk Mill dam was originally built to provide mechanical power, but hydroelectric generating facilities were installed in 1984.  Now, the Sparhawk project can produce 270 kilowatts of power, and operates under a licensing exemption issued by the Federal Energy Regulatory Commission in 1985.

Today the town of Yarmouth owns the dams, and is considering their future.  The Sparhawk dam is reportedly not producing much -- if any -- revenue for the town, while both dams may need maintenance and repairs.  Some community members suggest dam removal for reasons ranging from municipal fiscal policy to enhancing fish passage along the Royal River.  Others point to value of the Royal River's continuing ability to produce renewable hydroelectricity, and urge that the dams be maintained.  The East Elm Street dam could even have electric generation facilities installed, either traditional hydroelectric or hydrokinetic devices.

The community forum starts at 7 p.m. on November 1 at Yarmouth Town Hall.